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mbraun777

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About mbraun777

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    TT Member

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    Louisiana
  1. mbraun777

    Yamaha YZ250F 2003

    I purchased the MX version because it was a lighter bike than the enduro. Aside from the bolt-on parts you see from the pics, I installed a heavier flywheel to tame the power and a racing piston (just because I could). Additionally I had the forks and shock tuned for woods riding and my weight. I have about 20 hours on this engine rebuild.The MX gear ratios and the 'skinny' back tire are not ideal for enduro but you get used to that. There are times I've wished I had gotten the enduro because of the electric start. When you're on a steep hill and the engine kills, it would be really nice not to have to kick the thing back to life. Hey, I'm old school. We never had that stuff in the '70s.Love this bike. Probably never sell it. Still runs like new. Of course I keep it that way.
  2. mbraun777

    Yamaha YZ250F (2003)

    0 comments

    I purchased the MX version because it was a lighter bike than the enduro. Aside from the bolt-on parts you see from the pics, I installed a heavier flywheel to tame the power and a racing piston (just because I could). Additionally I had the forks and shock tuned for woods riding and my weight. I have about 20 hours on this engine rebuild.The MX gear ratios and the 'skinny' back tire are not ideal for enduro but you get used to that. There are times I've wished I had gotten the enduro because of the electric start. When you're on a steep hill and the engine kills, it would be really nice not to have to kick the thing back to life. Hey, I'm old school. We never had that stuff in the '70s.Love this bike. Probably never sell it. Still runs like new. Of course I keep it that way.
  3. mbraun777

    250F Crank Cam-Gear Kinda Wimpy

    Yall are right. I should have changed the chain sooner. I had about 70 hard hours on it when I split the case. I still maintain that a gear that small could be surface hardened for extended life.
  4. mbraun777

    250F Crank Cam-Gear Kinda Wimpy

    I've looked into cryo treatment. It will give a good thru-thickness increase in toughness. For gears I'd think that surface treatment would be better.
  5. As most have I have replaced my crank because of wear on the cam chain gear. It's enough of a pain that it has me thinking of going to a 450F because of the tougher parts not to mention HP. Has anyone tried to carburize or nitride that gear for wear resistance? I'm guessing that the crank would need to be rebalanced. Possibly there is an aftermarket crank that is already tough as nails.
  6. mbraun777

    what oil is everyone running

    I am a fan of AMSoil and Shell Rotela T but I recently switched to recycled John Deer tractor oil. It's gotta be John Deer!
  7. mbraun777

    Anybody dropped down from a 450?

    I toyed with going to a 450F for a while but I don't want the extra weight to sling around in the woods. My brother and his friend both bought CRF 450X having been on CRF 250X prior to that. My brother said the 450 makes him a better rider. His friend is selling the 450X I assume because of the weight and bought the KTM 300 s-smoke e-start. I will stick with the 250F with 18" rear tire, heavier flywheel, and 290 kit just for the fun factor.
  8. I don't believe it was mentioned already but make sure to get tapered feeler gages for checking valves. Otherwise you will have to cut the blades yourself.
  9. mbraun777

    Williams MotoWerx modded 07YZ250F

    It works for golf balls and the price seems to be reasonable. Anyone have a track record with these valves?
  10. mbraun777

    What pipe is the best???

    I have got to get one like that for my YZF!
  11. mbraun777

    What pipe is the best???

    I saw someone put a megaphone on his pipe.
  12. mbraun777

    After market valves for YZ 250 F

    You do have a point. These bikes require periodic maintenance after few riding hours. Their big brothers the 450F's can go a bit longer. You are going to be in the engine every year to replace the cam chain and inspect your valve clearance at a minimum. As far as cranks go I was crazy religious about oil changes (3 to 6 hours max), cam chains, and got less than 200 hrs out of the first one. Seems we can't escape replacing parts on these high strung engines.
  13. mbraun777

    After market valves for YZ 250 F

    Stainless steel valves need heavier springs to keep them from floating at high RPM because of the increase in mass. Honda's need SS valves because the titainium valves they make are trash and wear out in no time. If you ride Yamaha, stick with OEM valves.
  14. mbraun777

    Crank Timing

    Thumbs up for asking such a pertinent question. I wonder how many just never thought that through? Can you imagine how many would be in the weeds if that baby fired once every two cycles? I can see the threads "Engine Won't Start; Need Help FAST!" about one evert 10 minutes.
  15. mbraun777

    Interesting question (ethanol)

    Alcohol has a lower BTU rating than gas. So for more bang for your buck it needs to be gasoline.
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